Engines for the new Mini Cooper will be built at BMW’s Hams Hall works on the outskirts of Birmingham.

Production facilities at the massive Coleshill complex are undergoing a multi-million pound transformation to cater for the project.

The work will enable it to produce the brand new three and four cylinder engines including the 1.5 litre turbo for the much-anticipated new Mini Cooper, which will be unveiled at the car giant’s Cowley works on Monday before glittering launches at motor shows in Los Angeles and Tokyo on Wednesday.

Once redevelopment work on the Hams Hall facility is completed, the new eco-friendly engines for the much of the BMW fleet will be assembled at the plant, which is exciting news for component manufacturers across the West Midlands.

It is thought Hams Hall beat off challenges from other BMW factories in Germany and Austria to be the European production site for the engines, although they will also be rolled out at sites on other continents.

Hams Hall opened in February 2001 and its high-tech production facilities are being upgraded to manufacture and assemble BMW’s new generation of eco-focused internal combustion engines.

It currently builds engines for the BMW 1 Series, F30 3 Series and X1, plus all Mini variations.

The engine production facility at Hams Hall was the first BMW engine plant to be built outside Germany and Austria, recognising the importance of the UK as a major world economy and one of the BMW Group’s largest markets.

It is a major boost for Birmingham which has a long historical association with the iconic Mini.

The original car was designed and developed at the former Austin Works in Longbridge from 1959 until the last model rolled off the production line in 2000 before the marque was taken over by BMW.

The German-owned firm plans to develop a “new generation fo engines” to be built at Hams Hall. The crank-shafts for the new engines are already under production at Hams Hall and this will be followed by cylinder heads and blocks before full engine assembly gets underway.

The engine’s modular design means it will be adapted to fit any number of different models.

An insider at the plant said it was difficult to say exactly when full production of the new modular engines would start at Hams Hall.

“It will be part of a global network of facilities where the engines are assembled,” said a spokeswoman.

“Lots of work is still to be done because the plant is undergoing a complete transformation in this major development of production facilities. This is a transitional phase,” she said.

“When the work is finished we will be producing our next generation of engines at the plant for a whole range of vehicles.”

The first official glimpse of the new model will be caught at its UK debut on Monday - ironically on what would have been the 107th birthday of the original Mini’s designer Sir Alec Issigonis.

The new Mini will be built at the Oxford factory, although additional production will also start in the Netherlands in 2014 given the likely demand for the new model.

It will use components manufactured at the company’s Swindon pressing plant as well as the new line of turbo-charged three-cylinder petrol and diesel engines made at Hams Hall. It will sit on a new platform that will be used for an expanded Mini family, and will also be the basis for a forthcoming range of front-wheel-drive BMW 1-Series models.

BMW took over the Rover Group in 1984 but jettisoned many of the troubled Birmingham firm’s models. However it decided to retain the profitable Mini marque.

The last Mini - a red Cooper Sport - was built in October 2000 and presented to the British Motor Industry Heritage Trust in December of that year.

A total of 5,387,862 cars had been manufactured. The new BMW Mini is technically unrelated to the old car but retains the classic elements of the original design.